Robust incident tracking is not just good practice. It is crucial for protecting your most valuable asset: your employees. This guide demystifies three key metrics, Total Recordable Incident Frequency (TRIF), Lost Time Injury Rate (LTIR), and Days Away, Restricted, or Transferred (DART) rate, covering what each represents, how it is calculated, and why the nuances matter.
Why Incident Tracking Matters
Beyond regulatory compliance, meticulous incident tracking lets organizations identify trends and root causes, measure the effectiveness of their safety programs, benchmark performance against industry averages, promote a culture of safety through transparent reporting, and reduce the significant costs (lost productivity, medical expenses, insurance premiums, legal fees) that incidents create.
Total Recordable Incident Frequency (TRIF)
TRIF provides a broad overview of safety performance. It represents the number of recordable injuries and illnesses per 200,000 hours worked, regardless of severity. A recordable incident is generally any work-related injury or illness requiring medical treatment beyond first aid, resulting in lost workdays, restricted work, job transfer, or a fatality. The 200,000-hour factor represents 100 employees working 40 hours per week for 50 weeks.
TRIF = (Number of Recordable Incidents / Total Hours Worked) x 200,000
For example, a company with 150 employees that works 300,000 hours in a year and has 10 recordable incidents:
TRIF = (10 / 300,000) x 200,000 = 6.67
That is roughly 6.67 recordable incidents per 200,000 hours worked. Best practice is to collect data consistently per regulatory guidelines, thoroughly investigate every recordable incident for root cause rather than just counting it, analyze trends over time, and benchmark against similar organizations.
Lost Time Injury Rate (LTIR)
LTIR focuses on more severe incidents: those where an employee cannot return to work on their next scheduled shift. It measures injuries or illnesses that lead to at least one full day or shift missed beyond the day of injury, typically per 200,000 hours worked.
LTIR = (Number of Lost Time Injuries / Total Hours Worked) x 200,000
Using the same company, if 3 of the 10 recordable incidents resulted in lost time:
LTIR = (3 / 300,000) x 200,000 = 2
That is 2 lost time injuries per 200,000 hours worked. Best practice is to define "lost time" clearly and consistently, implement strong return-to-work programs, focus on preventing severe injuries, and track total lost days to understand full impact.
Days Away, Restricted, or Transferred (DART) Rate
Many safety professionals now consider DART a more holistic and accurate representation of overall safety performance, because it captures a broader spectrum of severity. The DART rate encompasses incidents resulting in days away from work, restricted work activity (the employee returns but cannot perform all regular duties), or job transfer (temporary or permanent reassignment due to injury or illness), typically per 200,000 hours worked.
DART Rate = (Number of Incidents Resulting in Days Away, Restricted Work, or Job Transfer / Total Hours Worked) x 200,000
Continuing the example, with 3 incidents resulting in days away, 2 in restricted work, and 1 in job transfer:
Total DART incidents = 3 + 2 + 1 = 6 DART Rate = (6 / 300,000) x 200,000 = 4
The DART rate here is 4. Best practice is to accurately record restricted duty and transfers (where many organizations fall short), focus on early intervention, investigate every DART incident thoroughly, train employees and management on what constitutes a DART incident, and use the data to manage high-risk tasks proactively.
Why DART Is a Better Representation of Overall Safety Performance
While TRIF and LTIR each have their place, DART offers a more comprehensive and arguably more accurate picture:
- Broader scope of impact: It captures incidents that may not cause lost time but still significantly alter an employee's ability to do their job.
- Reveals hidden costs: Restricted work and job transfers still incur costs from reduced productivity, retraining, and administrative burden.
- Focus on functionality: DART emphasizes an employee's functional capacity after injury, giving a more nuanced view of true impact.
- Encourages proactive management: By including restricted duty, it pushes organizations toward effective modified-work programs and early injury management.
- Reflects early intervention: A lower DART rate can signal that an organization is helping employees return to modified duties sooner, a sign of a mature, responsive safety program.
- Reduced incentive to underreport: There is sometimes unofficial pressure to keep LTIR low, which can lead to significant injuries being overlooked or not recorded as restricted duty. DART's broader definition helps counter that by valuing all injuries that alter work capacity.
Implementing a Robust Incident Tracking System
Whichever metrics you prioritize, the foundation is a robust tracking system. That starts with clear reporting procedures: make it easy for employees to report incidents, near misses, and hazards through accessible channels, emphasize timely reporting, and foster a no-blame culture where the goal is learning and prevention rather than punishment. It continues with thorough investigation and root cause analysis on every recordable and DART incident, documented corrective actions with follow-up to confirm effectiveness, and periodic review of the data to spot trends and drive continuous improvement.
The metrics you track shape the behaviour you get. Chasing a single lagging number can quietly encourage underreporting, while a broader, honestly recorded measure like DART keeps the focus where it belongs: on preventing harm and protecting people.
If you want help building an incident tracking and investigation system that measures what matters, TruStar Safety can help.